Margaret Thatcher’s key foreign policy adviser has mocked commentators rejoicing over the decision to change the colour of the British passport, describing it as nostalgia driven by ageing Eurosceptics.

Confirming it was Thatcher’s government who “chose” to ditch the blue passport in the 1980s – under no pressure from the European Union – Charles Powell said the clamour for the old-style travel document was “part of the nostalgia on which the predominantly elderly Brexit constituency thrives”.

May had sought to end a mostly fraught political year on a triumphant note by announcing the return of navy passports after Brexit, describing them an expression of “independence and sovereignty”. However, by Saturday morning, her move to change the colour of new passports in 2019 was being attacked by some as a PR stunt, as it became clear there is no Brussels legislation stating that EU countries’ passports had to be a certain colour.

Powell rebuked politicians and commentators who have greeted the announcement, saying: “So long as they are content with symbols, rather than substance, I see no harm in letting them have their way. Perhaps we should go the whole hog and reintroduce ambassadorial dress uniforms, as well as bowler hats and stiff collars for senior civil servants.”

Powell, who served as private secretary to Thatcher from 1983 to 1990, added: “If we get their agreement to full alignment with the single market in return, it’s a good deal.”

The European parliament’s chief Brexit coordinator, Guy Verhofstadt, claimed that the decision to change passport colour as a victory for Brexit was mendacious, tweeting that “the UK could have had any passport colour it wanted and stay in the EU”.

David Lammy MP went further, describing the move as “embarrassing”, claiming: “Brexit is beginning to feel like a huge effort to turn the clock back 100 years with some misguided imperial overtones.”

Scottish first minister Nicola Sturgeon was another who tweeted that the episode risked further damaging UK’s reputation on the world stage, denouncing the return of the navy blue passport as “insular, inward-looking, blue passport-obsessed nonsense”.

Labour MP Chuka Umunna said: “What utter nonsense. This belittles our country and your office.” The party’s former leader, Ed Miliband, added: “It is an expression of how mendacious, absurd and parochial we look to the world.”

Other critics included Wikipedia’s co-founder Jimmy Wales who said: “Can’t wait to tell my 2 [sic] British children that although they are losing the right to live and work throughout Europe, they get to get a blue passport.”

Although the announcement had been enthusiastically received at first by Brexit supporters, who had campaigned for a return to navy, some advocates were still not satisfied.

An article in the Daily Telegraph bemoaned that the shade of colour was not quite right, noting that mock-ups of the new passports showed it to be blue, but “that the pre-1988 passports appeared to be very dark blue, if not black”.

The tendering process for printing the passports is expected to take place under existing EU procurement rules, something that the current British contractor, De La Rue, recently admitted could mean they were produced abroad. The prospect has prompted many pro-Brexit figures to speak out, including Jacob Rees-Mogg, who tweeted: “Symbolism is important and I hope it will be printed in the UK too.”